A search of prior patents reveals that many devices for use in the grinding of valve seats are known. A patent to Ellenbogen, U.S. Pat. No. 3,039,242 for instance, teaches a seat refacing tool for use with valves which control liquid and gas flow. The invention in said patent, however, does not provide means for precisely securing and aligning a grinding element to and with respectively a valve casing and valve seat so as to guarantee flush contact between the grinding element and the valve seat. Use of the Ellenbogen invention can lead to uneven grinding of a valve seat, as a result.
Further research of prior patents reveals a valve seat grinder in U.S. Pat. No. 1,747,085 to Roy. The invention in Roy provides an apparatus for use in grinding valve seats in automobile engines and the like. The invention provides a rotatable shaft within a hand-held body element. The hand-held body element embraces the rotatable shaft by way of bearings, and the rotatable shaft is securely mounted within the hand-held body element. The rotatable shaft, on one end thereof, has a grinding element and on the opposite end thereof a means for attachment to a rotation producing driver machine. As in the Ellenbogen invention the Roy invention, while providing means for applying a rotating grinding element at a valve seat location, fails to provide a means by which the grinding element can be secured to and aligned with a valve casing apparatus and valve seat, respectively, so as to guarantee flush contact between the grinding element and the valve seat.
A need exists for a simple and easy to use apparatus which can be secured to liquid and gas flow controling valve casings, which apparatus provides a rotating grinding element at the location of a valve seat in flush contact therewith.